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Reclaimed water
to irrigate plants in public parks and municiple landscapes.]] Reclaimed water, sometimes called recycled water, is former wastewater (sewage) that has been treated to remove solids and certain impurities, and then used in Sustainable landscaping irrigation or to recharge groundwater aquifers. These are done,for sustainability and water conservation, rather than discharge the treated wastewater to surface waters such as rivers and oceans. The recycling and recharging is often done by using the treated wastewater for designated municipal sustainable gardening irrigation applications. In most locations, it is intended to be only used for nonpotable uses, such as irrigation, dust control, and fire suppression. There is debate about possible health and environmental effects with its uses. However, Los Angeles County's sanitation districts have provided treated wastewater for landscape irrigation in parks and golf courses since 1929. The first reclaimed water facility in California was built at San Francisco's Golden Gate Park in 1932. The Irvine Ranch Water District and Orange County Water District in Southern California are becoming the leaders in reclaimed water through their 'Green Acres Project.' Also in Orange County, and in other locations such as Singapore, water is given more advanced treatments and is used indirectly for drinking.NEWater FAQ, accessed 8 January 2007.Orange County Water District's Groundwater Replenishment System, accessed 6 March 2009 History Storm and sanitary sewers were necessarily developed along with the growth of cities. By the 1840s the luxury of indoor plumbing, which mixes human waste with water and flushes it away, eliminated the need for cesspools. Odor was considered the big problem in waste disposal and to address it, sewage could be drained to a lagoon, or "settled" and the solids removed, to be disposed of separately. This process is now called "primary treatment" and the settled solids are called "sludge." At the end of the 19th century, since primary treatment still left odor problems, it was discovered that bad odors could be prevented by introducing oxygen into the decomposing sewage. This was the beginning of the biological aerobic and anaerobic treatments which are fundamental to waste water processes. By the 1920s, it became necessary to further control the pollution caused by the large quantities of human and industrial liquid wastes which were being piped into rivers and oceans, and modern treatment plants were being built in the US and other industrialized nations by the 1930s.P.F.Cooper,2001, Decentralized Sanitation and Reuse, Chapt.2, IWA Publishing, London,UK. Designed to make water safe for fishing and recreation, the Clean Water Act of 1972 mandated elimination of the discharge of untreated waste from municipal and industrial sources, and the US federal government provided billions of dollars in grants for building sewage treatment plants around the country. Modern treatment plants, usually using sand filtration and chlorination in addition to primary and secondary treatment, were required to meet certain standards.33 Usc 1251 seq., 1972, Federal Water Pollution Control Act, Enacted by Congress. Current treatment improves the quality of separated wastewater solids or sludge. The separated water is given further treatment considered adequate for non potable use by local agencies, and discharged into bodies of water, or reused as reclaimed water. In places like Florida, where it is necessary to avoid nutrient overload of sensitive receiving water, reuse of treated or reclaimed water can be more economically feasible than meeting the higher standards for surface water disposal mandated by the Clean Water Act Sierra Club Fact Sheet Maximum Water Recovery To determine Maximum Water Recovery there are various techniques that have been developed by researchers; for maximum water reuse/reclamation/recovery strategies such as water pinch analysis. The techniques helps a user to target the minimum freshwater consumption and wastewater target. It also helps in designing the network that achieves the target. This provides a benchmark to be used by users in improving their water systems. Benefits The cost of reclaimed water exceeds that of potable water in many regions of the world, where a fresh water supply is plentiful. However, reclaimed water is usually sold to citizens at a cheaper rate to encourage its use. As fresh water supplies become limited from distribution costs, increased population demands, or climate change reducing sources, the cost ratios will evolve also. Using reclaimed water for non-potable uses saves potable water for drinking, since less potable water will be used for non-potable uses. It sometimes contains higher levels of nutrients such as nitrogen, phosphorus and oxygen which may somewhat help fertilize garden and agricultural plants when used for irrigation. The usage of water reclamation decreases the pollution sent to sensitive environments. It can also enhance wetlands, which benefits the wildlife depending on that eco-system. For instance, The San Jose/Santa Clara Water Pollution Control Plant instituted a water recycling program to protect the San Francisco Bay area's natural salt water marshes.http://www.epa.gov/region09/water/recycling/ Concerns Recent studies support long standing concerns about possible public health effects of reclaimed water. It has been known for some time that treated waste water effluent, or reclaimed water, contains pathogens that could be transferred to people through contact, including aerosols from sprinklers. Particularly worrisome are high levels of parasites such as giardia and cryptosporidium which are not killed by chlorination. Drip and subsurface irrigation technology applications circumvent this. Gennaccaro, McLaughlin, Betancourt, Huffman and Rose, Infectious Cryptosporidium parvum Oocysts in Final Reclaimed Effluent, Dept Marine Science, U of South Florida, St Petersburg, Florida. In 1997, the United States Environmental Protection Agency warned, "(Viable) bacteria from reclaimed water in sprinklers can travel more than 1000 feet in the air." EPA Guidelines for Water Reuse, (1996) As far back as 1984, researchers concluded that disinfection by chlorination, an important part of wastewater treatment, initially lowers the total number of sewage related bacteria, but may substantially increase the proportions of antibiotic resistant, potentially pathogenic organisms.GE Murray, RS Tobin, B Junkins, DJ Kushner,(1984) Effect of Chlorination on antibiotic resistance profiles of sewage-related bacteria, Appl Environ Microbiol. July 1998:48(1): 73-74 More recently, Chang (2007) reported that Staphylococcus aureus bacteria (responsible for MRSA) become more virulent and drug resistant after chlorination.Matthew Wook Chang, Freshteh Toghrol, William Bentley, Toxicogenomic Response to Chlorination Includes Induction of Major Virulence Genes in Staphylococcus aureus,Environ. Sci. Technol., 41(21)7570-7575. A large study in 2006 confirms that microbes, inactivated but not killed by treatment, can regrow in retention ponds and pipes, becoming a major source of the spread of multi-drug resistant pathogens in the environment.Timothy Lapara, Sara Firl,(2006) The Importance of Municipal Sewage Treatment in the Spread of Antibiotic resistance,100th General Meeting of the American Society for Microbiology, May 21–25, 2006. Orlando Fl. During the processing of reclaimed water, fragments can be released from microbes when their cell walls are disrupted. These fragments are not alive and not affected by disinfectants like chlorine. This intact genetic material can transfer both virulence and drug resistance to living microorganisms in water or soil. Amy Pruden (2006) demonstrates that such genetic fragments pass through sewer water reclamation plants into rivers and into drinking water sources.Amy Pruden, 2006, Antibiotic Resistance genes as emerging contaminants, Studies in Northern Colorado, Environmental Science Technology 40, 7445-7450 Since the number and types of bacteria in a treatment plant are large, and are exposed to antibiotic pharmaceuticals in wastewater, a positive environment exists for transfer of drug resistance. Independent scientists found that Santa Barbara's reclaimed water contained chlorine resistant bacteria that were also resistant to eleven of the twelve antibiotics tested.Edo Mcgowan, (2008) The Watchers.US/edo_politics-reclaimed-water.html-74k There is also concern in the industry about organic chemicals, including endocrine disruptors in wastewater.Maria Burke (2004),UK to tackle Endocrine Disruptors in Wastewater, Technology News, September 1,2004. In 2005, the United States Department of Agriculture reported: "Overall, the environmental and public health impacts of irrigation with reclaimed sewage effluent and the potential degradation of underlying groundwater are largely unknown." US Dept of Agriculture, 2005 Report Distribution and demand Reclaimed water is often distributed with a dual piping network that keeps reclaimed water pipes completely separate from potable water pipes. In the United States, reclaimed water is always distributed in lavender (light purple) pipes to distinguish it from potable water.Rules and Regulations for Reclaimed Water. City of San Diego. 31 January 2007.Purple Rain Education Program. Pasco County, Florida. 31 January 2007. In many cities using reclaimed water, it is now in such demand that consumers are only allowed to use it on assigned days. Some cities that previously offered unlimited reclaimed water at a flat rate are now beginning to charge citizens by the amount they use. Testing standards Reclaimed water is not regulated by the EPA but by the states, using standards formulated decades ago. Newer information shows serious public health concerns about pathogens in the water.Timothy LaPara, Sara Firl, 2006, The Importance of Municipal Sewage Treatment in the spread of Antibiotic resistance, 106th General Meeting of the American Society for Microbiology. Many pathogens cannot be detected by currently used tests.James D. Oliver, 2005, The Viable but Nonculturable State in Bacteria, J. of Microbiology p.93-100. Recent literature also questions the validity of testing for "indicator organisms" instead of pathogens.Valerie J. Harwood, Audry D. Levine, Troy M. Scott, Joan G. Rose, 2005,Validity of the Indicator Organism Paradign for Pathogen Reduction in Reclaimed Water and Public Health Protection, Applied and Environmental Microbiology, Vol.71. Nor do present standards consider interactions of heavy metals and pharmaceuticals which may foster the development of drug resistant pathogens in waters derived from sewage. Potable uses In most locations, reclaimed water is not directly mixed with potable (drinking) water for several reasons: *Utilities providing reclaimed water for nonpotable uses do not treat the water to drinking water standards. *Varying amounts of pathogens, pharmaceutical chemicals (e.g., hormones from female hormonal contraception) and other trace chemicals are able to pass through the treatment and filtering process, potentially causing danger to humans. Modern technologies such as reverse osmosis may help to somewhat overcome this problem. An experiment by the University of New South Wales reportedly showed a reverse osmosis system removed ethinylestradiol and paracetamol from the wastewater, even at 1000 times the expected concentration.From the Toilet to the Tap, Australian Broadcasting Corporation 9 November 2006 *Drinking water standards were developed for natural ground water, and are not appropriate for identifying contaminants in reclaimed water. In addition to pathogens, and organic and endocrine disrupting chemicals, a large number of compounds may be present in reclaimed water. They cannot all be tested for, and there is a paucity of toxicity information on many of the compounds.Committee on the Viablility of Augmenting Drinking Water Supplies with Reclaimed water, 1998, Issues in Potable Reuse, National Research Council Because of this, state regulatory agencies do not allow reclaimed water to be used for drinking, bathing, or filling swimming pools. They also warn those who use reclaimed water for irrigation to place a sign on their property warning people not to drink from the irrigation system, and to not use it directly on fruits or vegetables. Aboard the International Space Station, astronauts have been able to drink recycled urine due to the introduction of the ECLSS system. The system cost $250 million and has been working since May 2009. The system recycles wastewater and urine back into potable water used for drinking, food preparation, and oxygen generation. This cuts back on the need for resupplying the space station so often.Space.com. (2009, May 20). Astronauts Drink Recycled Urine, and Celebrate. Retrieved November 29, 2009 from http://www.space.com/missionlaunches/090520-space-urine.html Indirect Potable use Some municipalities are now investigating Indirect Potable Use (IPU) of reclaimed water. For example, reclaimed water may be pumped into (subsurface recharge) or percolated down to (surface recharge) groundwater aquifers, pumped out, treated again, and finally used as drinking water. This technique may also be referred to as groundwater recharging. Unplanned Indirect Potable use Unplanned Indirect Potable UsePublic Utilities Board, Overseas Experiences, accessed 24 April 2007. has existed even before the introduction of reclaimed water. Many cities already use water from rivers that contain effluent discharged from upstream sewage treatment plants. There are many large towns on the River Thames upstream of London (Oxford, Reading, Swindon, Bracknell) that discharge their treated sewage into the river, which is used to supply London with water downstream. This phenomenon is also observed in the United States, where the Mississippi River serves as both the destination of sewage treatment plant effluent and the source of potable water. Research conducted in the 1960s by the London Metropolitan Water Board demonstrated that the maximum extent of recycling water is about 11 times before the taste of water induces nausea in sensitive individuals. This is caused by the build up of inorganic ions such as Cl-, SO42-, K+ and Na+, which are not removed by conventional sewage treatment. Space travel Wastewater reclamation can be especially important in relation to human spaceflight. *In 1998, NASA announced it had built a human waste reclamation bioreactor designed for use in the International Space Station and a manned Mars mission. Human urine and feces are input into one end of the reactor and pure oxygen, pure water, and compost (humanure) are output from the other end. The soil could be used for growing vegetables, and the bioreactor also produces electricity.University of ColoradoScientific American Frontiers Treatment improvements As world populations require both more clean water and better ways to dispose of wastewater, the demand for water reclamation will increase. Future success in water reuse will depend on whether this can be done without adverse effects on human health and the environment. In the United States, reclaimed waste water is generally treated to secondary level when used for irrigation, but there are questions about the adequacy of that treatment. Some leading scientists in the main water society, AWWA, have long believed that secondary treatment is insufficient to protect people against pathogens, and recommend adding at least membrane filtration, reverse osmosis, ozonation, or other advanced treatments for irrigation water.Fred Lee PhD, President American Water Works Association, Reuse Conference, 1996 Seepage of nitrogen and phosphorus into ground and surface water is also becoming a serious problem, and will probably lead to at least tertiary treatment of reclaimed to remove nutrients in future.Harvey H. Harper PhD., 2008, Good intentions gone awry?, 27th International Symposium of North American Lake Management Society, Orlando Florida Even using secondary treatment, water quality can be improved. Testing for pathogens using Polymerase Chain Reaction (PCR) instead of older culturing techniques, and changing the discredited fecal coloform "indicator organism" standard would be improvements. In a large study Joan Rose, et al., 2004 Reduction of pathogens, indicator bacteria, alternative indicators by wastewater treatment and reclamation process, WERF treatment plants showed that they could significantly reduce the numbers of parasites in effluent, just by making adjustments to the currently used process. But, even using the best of current technology, risk of spreading drug resistance in the environment through wastewater effluent, would remain. Some scientists have suggested that there need to be basic changes in treatment, such as using bacteria to degrade waste based on nitrogen (urine) and not just carbonaceous (fecal) waste, saying that this would greatly improve effectiveness of treatment.Peter Maier PhD, Is Sewage Properly Treated?, Peter Maier.Net Currently designed plants do not deal well with contaminants in solution (e.g. pharmaceuticals). "Dewatering" solids is a major problem. Some wastes could be disposed of without mixing them with water to begin with. In an interesting innovation, solids (sludge) could be removed before entering digesters and burned into a gas that could be used to run engines.Ken Stedman, 2007, Micromedia Filtration Inc helps Gold Village Come Clean, Press Release Emerging disinfection technologies include ultrasound, pulse arc electrohydrolic discharge, and bank filtration.Jess C. Brown and Andrew Salveson, 2007, Emerging Disinfection Technologies Florida Resources Journal, July 6. Another issue is concern about weakened mandates for pretreatment of industrial wastes before they are made part of the municipal waste stream. Some also believe that hospitals should treat their own wastes. The safety of drinking reclaimed water which has been given advanced treatment and blended with other waters, remains controversial. Other alternatives In urban areas where climate change has threatened long-term water security and reduced rainfall over catchment areas, using reclaimed water for indirect potable use may be superior to other water supply augmentation methods. One other commonly used option is seawater desalination. Recycling wastewater and desalinating seawater may have many of the same disadvantages, including high costs of water treatment, infrastructure construction, transportation, and waste disposal problems. Although the best option varies from region to region, desalination is often superior economically, as reclaimed water usually requires a dual piping network, often with additional storage tanks, when used for nonpotable use. A less elaborate alternative to reclaimed water is a greywater system. Greywater is wastewater that has been used in sinks, baths, showers, or washing machines, but does not contain sewage (see blackwater). In a home system, treated or untreated greywater may be used to flush toilets or for irrigation.Grey Water SydneyWater.com.au 31 January 2007. Some systems now exist which directly use greywater from a sink to flush a toiletWaterSaver Technologies Aqus Uses Sink Greywater for Toilet. Treehugger.com. October 7, 2006. Retrieved May 22, 2007. or even combine the two into one piece of furnitureToilet Lid Sink. Gaiam. Retrieved May 22, 2007.. Perhaps the simplest option is a rainwater harvesting system. Although there are concerns about the quality of rainwater in urban areas, due to air pollution and acid rain, many systems exist now to use untreated rainwater for nonpotable uses or treated rainwater for direct potable use. There are also concerns about rainwater harvesting systems reducing the amount of run-off entering natural bodies of water. Worldwide applications and acceptance The leaders in use of reclaimed water in the U.S. are Florida and California,UF Professor: Drought Highlights Value Of Reused Water. University of Florida News. May 24, 2000. with Irvine Ranch Water District as one of the leading developers. They were the first district to approve the use of reclaimed water for in-building piping and use in flushing toilets. As Australia continues to battle the 7-10 year drought, nationwide, reclaimed effluent is becoming a popular option. Two major capital cities in Australia, Adelaide and Brisbane, have already committed to adding reclaimed effluent to their dwindling dams. Brisbane has been seen as a leader in this trend, and other cities and towns will review the Western Corridor Recycled Water Project once completed. Goulbourn, Canberra, Newcastle, and Regional Victoria, Australia are already considering building a reclaimed effluent process. According to a EU-funded study, "Europe and the Mediterranean countries are lagging behind" California, Japan, and Australia "in the extent to which reuse is being taken up." According to the study "the concept (of reuse) is difficult for the regulators and wider public to understand and accept.""Reuse of water in the EU and the Mediterranean", by Bill McCann, Water 21, Journal of the International Water Association, April 2008, p. 42-44, quoting the Aquarec project Reclaimed water applications Indirect potable use *London, United Kingdom *Singapore (where it is branded as NEWater) *Payson, AZGreen Valley Park Lakes Groundwater Recharge Project. *The Torreele project in the Veurne coastal region of Belgium, which began operating in 2002 *Virginia Occoquan Reservoir - The Upper Occoquan Sewage Authority plant discharges its highly treated output to supply roughly 20% of the inflow into the Occoquan Reservoir, which provides drinking water used by the Fairfax County Water Authority - one of the three major water providers in the Washington, D.C. metropolitan area. Non-potable use *Sydney, AustraliaSydney Water Recycling Projects *Melbourne, AustraliaMelbourne Water Recycling Projects *Tucson, ArizonaReclaimed Water *Clark County, NevadaWater Reclamation *Clearwater, FloridaMaking the Connections: Reclaimed and Drinking Water Supplies *St. Petersburg, FloridaWater Systems Maintenance Mission Statement *San Diego, California (San Diego County)Recycled Water *Contra Costa County, CaliforniaDelta Diablo Sanitation District, Eastern Contra Costa County *Austin, TXAustin Water Utility *Caboolture and Maroochy (South East Queensland, Australia) LGA's currently provide Reclaimed water for industrial use (primarily capital works). Users must apply for a key to be able to access the compounds in which the outlets are located.Application form for access to Recycled Water (Caboolture) Proposed In some places, reclaimed water has been proposed for either potable or non-potable use: *South East Queensland, Australia (planned for potable use as of late 2010) Beattie scraps water poll amid 'Armageddon situation'. ABC News Online 28 January 2007.Beattie defends recycled water against "scare mongers". ABC News Online 26 January 2007. *Newcastle, New South Wales, Australia (proposed for non-potable use).Recycling plant brings region closer to being drought proof. ABC News 19 July 2006. *Canberra, Australian Capital Territory, Australia (proposed in January 2007 as a backup source of potable water)Recycled water a step closer for Canberrans. ABC News Online 31 January 2007. *Los Angeles, California - By 2019, the Los Angeles Department of Water and Power will build a plant to replenish their groundwater aquifer with purified waterhttp://articles.latimes.com/2008/jun/07/local/me-water7 in order to deal with the shortage of rain and snow fall, restricted water imports and local groundwater contamination http://mayor.lacity.org/villaraigosaplan/EnergyandEnvironment/LACITY_004503.htm. Enterprises * Brac Systems - Canada * Ecoplay - Netherlands See also *Dual piping *Greywater *Irrigation *Sustainable gardening *Sustainable landscaping *Water conservation *Category: Water Conservation *Xeriscaping *Hydrology and urban planning *Cost effective minimum water network *NEWater *Sustainable agriculture *Sustainable design *Sewage treatment *Water filtration *Water Pinch *Water management hierarchy External links *Waterwise A nonprofit non-governmental Organization dedicated to promoting the wise use of water. *WateReuse A nonprofit Organization whose mission is to advance the beneficial and efficient use of water resources using reclamation, recycling, reuse, and desalination. *Watchers Protecting the Environment A nonprofit Organization dedicated to finding the truth about reclaimed sewage water and sludge. *Help for Sewage Victims A nonprofit Organization dedicated to factual research for the protection of sewage victims. References Category:Water conservation Category:Water supply Category:Irrigation Category:Water and politics Category:Water and the environment Category:Water treatment Category:Sewerage Category:Sustainable technologies Category:Sustainable agriculture Category:Organic farming Category:Organic gardening Category:Landscape architecture fr:Réutilisation ou recyclage des eaux usées zh:中水